mkpost.mx raw

   1  // Copyright 2016 The Go Authors. All rights reserved.
   2  // Use of this source code is governed by a BSD-style
   3  // license that can be found in the LICENSE file.
   4  
   5  //go:build ignore
   6  
   7  // mkpost processes the output of cgo -godefs to
   8  // modify the generated types. It is used to clean up
   9  // the syscall API in an architecture specific manner.
  10  //
  11  // mkpost is run after cgo -godefs by mkall.sh.
  12  package main
  13  
  14  import (
  15  	"fmt"
  16  	"go/format"
  17  	"io"
  18  	"log"
  19  	"os"
  20  	"regexp"
  21  	"bytes"
  22  )
  23  
  24  func main() {
  25  	b, err := io.ReadAll(os.Stdin)
  26  	if err != nil {
  27  		log.Fatal(err)
  28  	}
  29  	s := string(b)
  30  
  31  	goarch := os.Getenv("GOARCH")
  32  	goos := os.Getenv("GOOS")
  33  	switch {
  34  	case goarch == "s390x" && goos == "linux":
  35  		// Export the types of PtraceRegs fields.
  36  		re := regexp.MustCompile("ptrace(Psw|Fpregs|Per)")
  37  		s = re.ReplaceAllString(s, "Ptrace$1")
  38  
  39  		// Replace padding fields inserted by cgo with blank identifiers.
  40  		re = regexp.MustCompile("Pad_cgo[A-Za-z0-9_]*")
  41  		s = re.ReplaceAllString(s, "_")
  42  
  43  		// We want to keep the X_ fields that are already consistently exported
  44  		// for the other linux GOARCH settings.
  45  		// Hide them and restore later.
  46  		s = bytes.Replace(s, "X__val", "MKPOSTFSIDVAL", 1)
  47  		s = bytes.Replace(s, "X__ifi_pad", "MKPOSTIFIPAD", 1)
  48  		s = bytes.Replace(s, "X_f", "MKPOSTSYSINFOTF", 1)
  49  
  50  		// Replace other unwanted fields with blank identifiers.
  51  		re = regexp.MustCompile("X_[A-Za-z0-9_]*")
  52  		s = re.ReplaceAllString(s, "_")
  53  
  54  		// Restore preserved fields.
  55  		s = bytes.Replace(s, "MKPOSTFSIDVAL", "X__val", 1)
  56  		s = bytes.Replace(s, "MKPOSTIFIPAD", "X__ifi_pad", 1)
  57  		s = bytes.Replace(s, "MKPOSTSYSINFOTF", "X_f", 1)
  58  
  59  		// Force the type of RawSockaddr.Data to [14]int8 to match
  60  		// the existing gccgo API.
  61  		re = regexp.MustCompile("(Data\\s+\\[14\\])uint8")
  62  		s = re.ReplaceAllString(s, "${1}int8")
  63  
  64  	case goos == "freebsd":
  65  		// Keep pre-FreeBSD 10 / non-POSIX 2008 names for timespec fields
  66  		re := regexp.MustCompile("(A|M|C|Birth)tim\\s+Timespec")
  67  		s = re.ReplaceAllString(s, "${1}timespec Timespec")
  68  	}
  69  
  70  	// gofmt
  71  	b, err = format.Source([]byte(s))
  72  	if err != nil {
  73  		log.Fatal(err)
  74  	}
  75  
  76  	// Append this command to the header to show where the new file
  77  	// came from.
  78  	re := regexp.MustCompile("(cgo -godefs [a-zA-Z0-9_]+\\.go.*)")
  79  	s = re.ReplaceAllString(string(b), "$1 | go run mkpost.go")
  80  
  81  	fmt.Print(s)
  82  }
  83